1. Field of the Invention
The present invention relates to an information storage medium including device-aspect-ratio information of a markup document, and a method and apparatus to play back audio and video (AV) data in an interactive mode using the markup document.
2. Description of the Related Art
Generally, markup documents are written in a markup language such as a hypertext markup language (HTML) or the like. The markup documents may be recorded on or played back from, for example, digital versatile discs (DVDs) via a personal computer (PC). Such DVDs are being sold in the market. Among these DVDs, an interactive DVD supports an interactive mode to show markup-document-based AV contents. Typically, contents recorded on the interactive DVD can be played back in two modes. One of the two modes is a video mode in which contents are displayed as from that of a general DVD. The other mode is an interactive mode in which contents are displayed via a display window defined by a markup document. For example, where a user selects an interactive mode, a web browser in a PC displays a markup document recorded on an interactive DVD, and a display window defined by the markup document displays the contents selected by the user. In other words, an AV picture is obtained from AV data and a markup picture is obtained from a markup document. The AV picture may be embedded in the markup picture to display an interactive picture in an interactive mode.
For example, where contents correspond to an AV data-made movie, the AV data-made movie may be shown in an AV picture, and various types of additional information such as scripts, stories, photos of actresses or actors, or the like may be displayed in a markup picture. The additional information may include a variety of resource files such as image files, text files, animation files, and the like.
FIGS. 1A, 1B, 1C, and 1D show types of pictures displayed on a display device during a playback from a conventional DVD. In particular, FIG. 1A shows a picture having an aspect ratio of 4:3. FIG. 1B shows a 4:3 letter box picture with blanks marked with slanted lines appearing in upper and lower portions thereof, where a 16:9 source picture is displayed on a 4:3 screen of the display device. FIG. 1C shows a 4:3 pan-scan picture to overcome the disadvantage of a size reduction of actual contents in the 4:3 letter box picture. In other words, relatively unimportant side portions of the 16:9 source picture are cut out to display the remaining source picture as a 4:3 picture. That is, only a portion of the source picture is shown to a user as the 4:3 letter box picture, while the cut portions are not shown to the user. The quality of the 4:3 pan-scan picture is dependent on how portions to be cut are determined, i.e., the user's skill. FIG. 1D shows a 16:9 picture.
In the conventional art, an interactive picture is fixedly displayed as one of the pictures of FIGS. 1A, 1B, 1C, and 1D. In this case, where a markup document recorded on an interactive DVD is displayed on a display device having a screen with an aspect ratio that is not fit for the markup document, a portion of data in a markup picture, such as texts, graphics, or the like, may be distorted.
FIGS. 2A and 2B illustrate a case where a markup document made as a 16:9 source picture is distortedly displayed in a 4:3 letter box picture. FIG. 2A illustrates a 16:9 source picture displayed on a 16:9 screen, and FIG. 2B illustrate a case where the 16:9 source picture is displayed as the 4:3 letter box picture. As shown in FIG. 2B, the size of an AV picture is reduced, whereas a markup picture containing texts, graphics or the like written in a HTML is displayed as is. Accordingly, a portion of the texts, graphics or the like may overlap blank portions of the 4:3 letter box picture and may not be shown to a user.